Cost-effectiveness of left atrial appendage closure with Watchman for non-valvular atrial fibrillation patients in Japan.

AIMS: Left atrial appendage closure (LAAC) has been demonstrated to be cost-saving relative to oral anticoagulants for stroke prophylaxis in patients with non-valvular atrial fibrillation (NVAF) in the United States and Europe. This study assessed the cost-effectiveness of LAAC with the Watchman device relative to warfarin and direct oral anticoagulants (DOACs) for stroke risk reduction in NVAF from a Japanese public healthcare payer perspective. METHODS: A Markov model was developed with 70-year-old patients using a lifetime time horizon. LAAC clinical inputs were from pooled, 5-year PROTECT AF and PREVAIL trials; warfarin and DOAC inputs were from published meta-analyses. Baseline stroke and bleeding risks were from the SALUTE trial on LAAC. Cost inputs were from the Japanese Medical Data Vision database. Probabilistic and one-way sensitivity analyses were performed. RESULTS: Over the lifetime time horizon, LAAC was less costly than warfarin (savings of JPY 1,878,335, equivalent to US $17,600) and DOACs (savings of JPY 1,198,096, equivalent to US $11,226). LAAC also provided 1.500 more incremental quality-adjusted life years (QALYs) than warfarin and 0.996 more than DOACs. In probabilistic sensitivity analysis, LAAC was cost-effective relative to warfarin and DOACs in 99.98% and 99.73% of simulations, respectively. LAAC dominated (had higher cumulative QALYs and was less costly than) warfarin and DOACs in 89.94% and 83.35% of simulations, respectively. CONCLUSIONS: Over a lifetime time horizon, LAAC is cost-saving relative to warfarin and DOACs for stroke risk reduction in NVAF patients in Japan and is associated with improved quality-of-life.

This study examined the cost-effectiveness of left atrial appendage closure (LAAC) compared to oral anticoagulants for stroke risk reduction among individuals with a specific type of irregular heart rhythm called non-valvular atrial fibrillation (NVAF). This study evaluated the cost-effectiveness of LAAC using the Watchman device in comparison to warfarin and direct oral anticoagulants (DOACs) from the perspective of Japan's public healthcare system. To investigate this, a computer-based model was developed involving 70-year-old patients over their lifetime. Data from notable studies such as the PROTECT AF and PREVAIL trials (covering 5 years) for LAAC and published meta-analyses for warfarin and DOACs were incorporated into the model. Baseline stroke and bleeding risks were derived from the SALUTE trial on LAAC. Cost inputs were based on data from the Japanese Medical Data Vision database. Additionally, we performed thorough cost-effectiveness analyses, including probabilistic and one-way sensitivity assessments. Our findings revealed that, over a lifetime, LAAC was more cost-effective than both warfarin and DOACs. Further, LAAC contributed an additional 1.500 quality-adjusted life years (QALYs) compared to warfarin and 0.996 QALYs compared to DOACs. In the long-term, adopting LAAC as an alternative to warfarin and DOACs is a cost-effective strategy for reducing stroke risk in NVAF patients in Japan. Moreover, it is associated with enhanced quality-of-life. These findings hold significant implications for informing decision-making in healthcare policies and clinical practices for NVAF patients.

Lesion size and adjacent tissue damage assessment with high power and short duration radiofrequency ablation: comparison to conventional radiofrequency ablation power setting.

There is increased interest in creating high-power short duration (HPSD) ablation lesions in the field of atrial fibrillation (AF) radiofrequency ablation (RFA). We evaluated the lesion characteristics and collateral damage using two separate RFA protocols setting (HPSD: 50 W and 7 s vs control: 25 W and 30 s) in vitro model. Sixteen freshly killed porcine hearts were obtained, and the atrium and ventricle slabs were harvested for ablation. The each slabs were placed in a tissue bath with circulating 0.9% NaCl at maintained temperature 37 °C. RFA was performed with 4 mm tip irrigated force sensing catheter. All lesions were ablated under recording the electrical parameters using with Ensite Navx system (St. Jude Medical, St. Paul, Minnesota). After RFA, lesion characteristics were assessed for each lesion. Thirty-five lesions were made for each ablation protocol (total 70 lesions for analysis). Ablation parameters were similar between two groups (HPSD vs control; impedance drop (Ω): 34.2 ± 13.1 vs 36.1 ± 8.65 P = 0.49, contact force (g): 13.9 ± 4.37 vs 14.6 ± 5.09, P = 0.51, lesion size index: 4.8 ± 0.52 vs 4.73 ± 0.59, P = 0.62). Although the lesion volume was similar, the HPSD ablation creates wider but more shallower lesions compared to control group (HPSD vs control; lesion volume: 29.6 ± 18.1 mm3 vs 35.5 ± 17.1 mm3 P = 0.16, lesion diameter: 4.98 ± 0.91 mm vs 4.45 ± 0.74 mm P = 0.0095, lesion depth: 2.2 ± 0.76 mm vs 2.8 ± 1.56 mm P = 0.046). Of these, 38 lesions were assessed for adjacent tissue damage and adjacent tissue damages were more frequent seen in control group (HPSD vs control; 1/19 (5.26%) vs 6/19 (31.5%), P = 0.036). Effective lesions were made with HPSD, thereby reducing RFA procedure time. Although the lesion volume was similar between two groups, collateral damage was less seen in HPSD group attributed by lesion characteristics.

Assessment of cyclic changes in the diameter of the aortic annulus using speckle-tracking trans-esophageal echocardiography.

It is uncertain whether dynamic variation in the diameter of the aortic annulus occurs during the cardiac cycle in humans. The purpose of this study was to analyze cyclic changes of the aortic annulus using speckle-tracking trans-esophageal echocardiography. The subjects were 40 patients with aortic stenosis and 40 controls. Absolute and relative changes in the diameter of the aortic annulus and the times at which the maximum and minimum diameters occurred during the cardiac cycle were determined using speckle-tracking trans-esophageal echocardiography. The maximum and minimum diameters were 22.9 ± 2.7 and 20.0 ± 2.9 mm, respectively, in controls. The change in diameter of the aortic annulus was 2.9 ± 0.7 mm, and the relative change was 12.9 ± 3.5%. The maximum aortic annulus diameter was reached at the onset of aortic valve opening, and the minimum diameter occurred in the rapid filling phase. The change in diameter of the aortic annulus was significantly smaller (2.2 ± 0.6 mm vs. 2.9 ± 0.7 mm, p < 0.0001), and the time to reach the maximum diameter was significantly longer (98.5 ± 17.5 ms vs. 83.4 ± 18.2 ms, p = 0.0004), in the aortic stenosis group than in the control group. The study found that dynamic changes of the aortic annulus occur in the cardiac cycle and can be measured using speckle-tracking trans-esophageal echocardiography. We also found that aortic stenosis has an effect on the extent and timing of these changes. This suggests that accurate assessment of aortic annulus diameter requires consideration of the timing of the cardiac cycle.

Multidetector CT coronary angiography for patient triage to invasive coronary angiography: Performance and cost in ambulatory patients with equivocal or suspected inaccurate noninvasive stress tests.

BACKGROUND: Multidetector-CT angiography (MDCTA) differs from noninvasive stress tests by directly imaging coronary anatomy. The utility of MDCTA for invasive triage is undefined however. We evaluated MDCTA triage to invasive coronary angiography in outpatients with indeterminate or suspected inaccurate stress tests, and estimated cost savings by MDCTA in this role. METHODS: Consecutive MDCTA patients were retrospectively compared with noninvasive stress tests if performed within 6 months of MDCTA. Twelve-month clinical follow up was obtained for patients not undergoing invasive angiography, and cost using MDCTA for triage to invasive coronary angiography was calculated. RESULTS: MDCTA was performed in 385 patients who had noninvasive stress testing. Stress tests include included treadmill (n = 37), stress echo (n = 178), and nuclear perfusion imaging (n = 170). Invasive angiography was performed in 57 (14.8%). MDCTA compared to CA showed positive and negative predictive values of 94%/100% respectively for lesions found by invasive QCA. Stress testing compared to MDCTA showed positive/negative predictive values of 100%/67% for treadmill exercise, 60%/54% for stress echo, and 59%/55% of nuclear perfusion examinations respectively. One year clinical follow up in 314 patients showed no coronary events in 98% (309) of patients. Triage to invasive angiography by MDCTA showed a 4-fold cost reduction. CONCLUSIONS: MDCTA shows excellent performance as a triage for invasive angiography in patients with stress tests that are equivocal or thought inaccurate. A negative CTA confers good 12-month prognosis. Substantial cost savings may accrue using MDCTA in this triage role.